Holding fixtures for type blanks



July 7, 1970 DEDEK ETAL 3,519,262

HOLDING FIXTURES FOR TYPE BLANKS Filed Nov. 16, 1967 2 Sheets-Sheet l INVENTORS.

FRANK DEDEK Fl 3 BY MELVIN 0. HINDEN AGENT July 7, 1970 DEDEK ETAL nowme mxwuans FOR mm BLANKS 2 Sheets-Sheet 2 Filed Nov. 16, 1967 INVENTORS. FRANK DEDEK y MELVIN 0. HINDEN AGENT United States Patent O 3,519,262 HOLDING FIXTURES FOR TYPE BLANKS Frank Dedek, Westland, and Melvin 0. Hinden, Detroit, Mich., assiguors to Burroughs Corporation, Detroit, Mich., a corporation of Michigan Filed Nov, 16, 1967, Ser. No. 683,518 Int. Cl. B23q 3/06 US. Cl. 269-47 Claims ABSTRACT OF THE DISCLOSURE A fixture for holding an apertured metal blank while subjected to metal working operations and particularly for gripping the slotted shank portion of a printing type blank while a print character is formed on the integrally connected head portion thereof. The fixture comprises a pair of assembled mating blocks which form a central chamber for receiving and, holding the slotted shank portion of a type blank while the head portion is shaped under dies to form a print character. One of the assembled blocks includes an element dirnensionably fitting the slot and movable thereinto to prevent slot deformation during the character forming operation. The slot fitting element has one end embedded in a resilient body which when acted on by an external force will urge the element into the slot and upon removal of the force will automatically withdraw the element from the slot.

BACKGROUND OF THE INVENTION Holding fixtures to hold and support objects which are to be operated upon have been employed in the prior art to fabricate a wide variety of products.

In the art relating to the fabrication of printing type, the prior art practice was to form a print character on the head end of a type blank and subsequently to fabricate a shank portion which contained a rectangular slot. The slot enabled the completed printing type to be mounted to a printing machine. The shank portion was fabricated after a print character was formed on the head portion in order to prevent metal flow into the slot during the character forming operation.

The holding fixture of the present invention overcomes the problem of metal flow into the slot by including a member which maintains the slot dimensions during the character forming operation, the fixture concurrently serving to clamp the shank portion of the blank. The slot maintaining feature of the fixture enables the shank portion of the type blank to be fabricated before the print characters are formed on the head portion. This procedure allows the printing type to be mass produced at a more economical cost.

SUMMARY OF THE INVENTION This invention relates to holding fixtures for gripping slotted metal blanks while metal Working operations are performed thereon and more particularly to such a fixture for gripping the already formed slotted shank of a printing type member while the integrally connected head portion thereof is die shaped to form a print character. The fixture includes a pair of mating blocks having stepped working faces which in assembled condition form a central chamber or cavity into which the shank of the type member is received and tightly gripped and which further form a shoulder which acts as a support for the print head portion during its character shaping operation.

In order to prevent metal in the shank from flowing during the character shaping operation on the head portion, which would affect the size and shape of the shanks slot, there is provided a movable element in one of the Patented July 7, 1970 mating blocks capable of entering the slot and being dimensionally shaped to fit the slot thus preventing any displacement or change in the size of the slot. To provide the desired movement of the element and at the same time avoid damage or breakage to the element in the event of misalignment of parts, one end of the element is embedded in a resilient body snugly fitting one of the blocks but capable of compression in the direction of the element to urge the same into the slot of the shank. A force external to the fixture may be employed to compress the resilient body and thereby project the element into the slot, the resilient body acting automatically to withdraw the element upon cessation of the compressing force.

It is the object of the invention to provide a fixture assembly for holding type blanks with integrally con nected head and slotted shank portions and for preventing slot deformation while a character is formed upon the head portion of the type blank.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of the assembled type blank holding fixture utilized in the present invention,

FIG. 2 is a perspective view of a plug utilized with the fixture,

FIG. 3 is a perspective view of the type blank holding fixture in its disassembled position,

FIG. 4 is a perspective and sectional view of the type blank holding fixture with a type blank held therein,

FIG. 5 is a plan view of the holding assembly with the plug inserted, the assembly shown clamped in a die holder cavity, and

FIG. 6 is a perspective view of a type blank after a print character is formed thereupon.

DESCRIPTION OF A PREFERRED EMBODIMENT Referring now to FIG. 1, there is shown the holding fixture utilized in the present invention. A process used to fabricate type blanks held in the holding fixture is described in Ser. No. 683,524, filed Nov. 16, 1967, now abandoned, of which Ser. No. 708,892, filed Feb. 28, 1968 is a continuation of common ownership. The holding fixture comprises a pair of mating blocks 28 and 29 having a series of step-like projections on their working faces. The assembled pair of mating blocks provides a central aperture or chamber 30 for receiving and holding the inserted type blank during the character forming operation. A cylindrical aperture 31 is formed on one side of the mating block 28. The aperture 31 extends partially through the thickness of the mating block 28. A narrow rectangular slot 32 is formed as shown in the remaining thickness of the mating block 28 and extends to chamber 30.

Referring now to FIG. 2, there is shown a plug 33 used with the holding fixture shown in FIG. 1. The plug 33 comprises metal disk 34, a body of resilient plastic material 35, such as Adeprene, and a headed pin 36 which includes a blade or knife shaped rectangular extension 37. Adeprene is a trademark describing a urethene elastomer manufactured by E. I. du Pont de Nemours and Company. Adeprene has high compression factor and good wearing qualities. Ordinary rubber or a steel spring could alternatively be used as the resilient body. The headed end of the pin 36 is embedded (or floats) within the resilient body 35 while the extension 37 projects beyond the body 35 and is dimensionally shaped to fit the slot 3 of the blank, as drawn in FIGS. 4 and 6.

Referring now to FIG. 3, there is shown the holding fixture in its disassembled condition, comprising mating blocks 28 and 29 having a series of step-like projections on their working faces. When assembled as shown in FIG. 1, the pair of mating blocks provide a central aperture or chamber for receiving and holding the inseited type blank during the character forming operation. Shoulders 38 and 39 on the assembled blocks cooperate to firmly support the lower end of the head portion of each inserted blank. Additional support for the type blank is provided by member 41 which is arranged to be inserted into the end of the central aperature 30 opposite that in which the type blank is inserted and to be held in contact with the type blank shank. The slot 32 opens through the mating block projection which forms shoulder 38, the slot 32 being positioned so that it will be coextensive with the rectangular slot 3 of each inserted type blank.

Referring now to FIG. 4, the head portion 1 of a type blank is shown being supported by shoulder 38 of the holding fixture. The plug 33 is inserted into aperture 31 in the mating block 28 and pressed therein by an external force so that the blade or rectangular knife edged extension 37 is forced through slot 32 and into the rectangular retaining slot 3 of the type blank. The extension 37 snugly fits the slot 3 and prevents unwanted metal flow into the slot 3 when the blank is subjected to the character forming operation and also provides support for the type blank. Additional support for the type blank is provided by member 41 which is held in contact against the end of the shank 2 opposite to the type blank head.

In order to facilitate the alignment of the two mating blocks 28 and 29, mating block 28 is shaped with a solid rectangular projection 42 extending crosswise to the type blank accommodating cavity 30 and which is slidably receivable in longitudinal recess 43 located in mating block 29.

Since portion of plug 33 is made of a resilient material, preferably Adeprene, the removal of the external force acting on the plug 33 enables the resilient mate rial to return to its original dimensions, thereby automatically withdrawing extension 37 from the elongated slot of the type blank and facilitating the removal of the type blank from the fixture after the character form: ing operation is completed. In the event that the slot in the type blank is misaligned with respect to the extension 37 or the plug thus preventing the extension 37 from passing into slot 3 of the blank, the resiliency of the body 35 is sufficient to enable the pin 36 to compress the body further and thus prevent blade damage or breakage.

Referring now to FIG. 5, there is shown a top view of the holder assembly of FIG. 1. The plug 33 has been inserted into the aperture 31. The holder assembly is placed in a cavity located within the holder A. A wedge shaped member B is also inserted into the cavity adjacent a complementing face of mating block 29. A member C, part of a clamping spindle D, is forced through an aperture E in the die holder and caused to exert pressure on wedge B, forcing the holder assembly against the opposite wall of the cavity. The wall exerts an opposing force on the metal disk 34 compressing the resilient body 35 and forcing extension 37 through slot 32 and into the central aperture 30. The extension 37 Will pass through slot 3 of each inserted type blank, thereby supporting the blank and also preventing metal flow into the slot.

Referring now to FIG. 6, a print character 44 is shown formed on the head portion 1 of a type blank. The excess metal 45 formed around the periphery of the head 1 is due to metal flow and can be removed in a separate trimming operation.

It is to be understood that the foregoing explanation is by way of illustration only. It will be apparent to those skilled in the art that various changes may be devised in the holding fixture assembly of the present invention for holding objects in the manufacture of devices other than printing types while utilizing the principles of the invention. Therefore it is intended that the invention include all variations of the specific holding fixture assembly which are within the proper scope and meaning of the appended claims:

What is claimed is:

1. In a holder assembly having a chamber for clamping the apertured shank portion of a printing type blank while the integrally connected head portion thereof is shaped under swaging pressures to form a printing character thereon, shoulder means within said chamber for supporting said type blank, and retractably movable rigid means extendable into said chamber and extending through said shank aperture and being dimensionally shaped to precisely fit the aperture for preventing shank aperture deformation and metal flow thereinto while the printing character is formed on the head portion of the blank.

2. The holder assembly as defined in clam 1, wherein said rigid means has one end thereof embedded in a body of resilient material.

3. A holder assembly for gripping apertured metal blanks while subject to metal-flowing pressures comprising, in combination, a pair of mating blocks cooperating to form when assembled together a chamber for receiving and tightly clamping an apertured metal blank, one of said blocks having a passage therein opening out through a side wall thereof and extending to and opening into the chamber in which the metal blank is received, a body of resilient material in said passage, and a member of rigid material located between the resilient body and the blank receiving chamber and having its outer end embedded in the resilient body.

4. The holder assembly as defined in claim 3 wherein said passage is divided into two sections of different crosssectional area, the larger of the two sections receiving said body of resilient material and the smaller section receiving said member of rigid material.

5. The holder assembly as defined in claim 4 also including means for exerting a force on said resilient body to thereby urge the member of rigid material into the aperture of the metal blank received in said chamber.

6. Apparatus for metal working comprising, in combination, a pair of mating blocks, each of said blocks having interfitting step-shaped projections on their working faces cooperating to provide a chamber for receiving and supporting an apertured part to be worked upon, one of said blocks having a cylindrically shaped recess opening out through a side wall. thereof and a noncylindrcial shaped passage from the base of the recess and opening into said chamber, a resilient plug in said recess and a blade-like member of rigid material having one end in engagement with the plug, said rigid member being movable into the chamber when a compressive force is exerted on said plug.

7. The apparatus as defined in claim 6 including a die holder and clamping spindle, the pair of mating blocks being placed within the die holder, said spindle being capable of exerting force to compress the resilient plug and thereby urge said blade-like member through the part aperture.

8. The apparatus as defined in claim 6 including means for exerting a force on said resilient plug to thereby urge the blade-like member to move into the aperture of the part received in said chamber.

9. Apparatus for clamping the apertured shank portion of a printing type blank while the integrally connected head portion thereof is being subjected to a character forming operation comprising, in combination, a pair of mating blocks cooperating to form when assembled together a chamber for receiving and tightly clamping the apertured printing type blank, one of said blocks having a passage therein divided into two sections of different cross-sectional area, said passage opening out through a side wall thereof and extending to and opening into the chamber in which said blank is received, a body of resili- 6 ent material located in the larger of the two sections, and References Cited a blade'like member of rigid material located in the smaller of said sections, said member having one end UNITED STATES PATENTS thereof embedded in said resilient body, the other end 2,996,391 8/1961 ekcler 299-92 thereof being movable into the chamber when a compressive force is exerted on said resilient body. 5 ROBERT RIORDON Pnmary Exammer 10. The apparatus as defined in claim 9 including D. D. EVENSON, Assistant Examiner means for exerting a force on said resilient body so that said blade-likemember moves into the type blank aper- US. Cl. X.R.

ture, said other end thereof dimensionally fitting the 269-287 aperture thereby preventing its deformation during the 10 character forming operation. 

